1. Field of the Invention
The present invention relates to a ring-shaped thrust bearing formed by stamping a plate.
2. Statement of the Related Art
A bush with a collar in which the collar is deformed into a corrugated shape in the direction of its thickness is disclosed in Japanese Utility Model Unexamined Publication No. 16442/1977. In this prior art, the collar is provided around the outer periphery of an end portion of a sleeve, and this bush with a collar constitutes a thrust and radial sliding bearing.
It is very difficult to manufacture thrust and radial sliding bearings as compared with manufacturing bearings without collars, so that it is very difficult to ensure high accuracy this type of bearing, and productivity is therefore low. Furthermore, according to normal usage, the radial bearing portions are used to support a high load, while the thrust bearing portions are used to support a low load. However, if the bush is constructed such as to be integrally formed with a collar, the same bearing material is inevitably used for the two portions, with the result that the costs become high.